Umbrella



FIG. 1 is a side view of an umbrella showing my new design, in a closed position;

FIG. 2 is a top perspective view, shown in an open position;

FIG. 3 is a bottom perspective view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof; and,

FIG. 6 is an exploded top perspective view thereof. 

The ornamental design for an umbrella, as shown and described. 